Dumping U8Plus Smartwatch ROM Via Vibration Motor
[Lee] continues with his exploration of the U8Plus (a cheap smartwatch). He hasn’t got it all cracked, yet, but he did manage to get a dump of the device’s ROM using an unusual method. At first, [Lee] thought that the JTAG interface (or, at least, the pins presumed to be the JTAG interface) would be a good way to explore the device. However, none of the people experimenting with the device have managed to get it to work.
Instead, [Lee] went through the serial bootloader and dumped the flash memory. He found out, though, that the bootloader refused to read …read more
Particle Electron – The Solution To Cellular Things
Just over a year ago, Particle (formerly Spark), makers of the very popular Core and Particle Photon WiFi development kits, released the first juicy tidbits for a very interesting piece of hardware. It was the Electron, a cheap, all-in-one cellular development kit with an even more interesting data plan. Particle would offer their own cellular service, allowing their tiny board to send or receive 1 Megabyte for $3.00 a month, without any contracts.
Thousands of people found this an interesting proposition and the Electron crowdfunding campaign took off like a rocket. Now, after a year of development and manufacturing, these …read more
Error Detection and Correction: Reed-Solomon, Convolution and Trellis Diagrams
Transferring data without error when there is a lot of background noise is a challenge. Dr. Claude E. Shannon in 1948 provided guidance with his theory addressing the capacity of a communications channel in the presence of noise. His work quickly spread beyond communications into other fields. Even other aspects of computer use were impacted. An example is the transfer of data from a storage medium, like a hard drive or CD-ROM. These media and their sensors are not 100% reliable so errors occur. Just as Shannon’s work defines communication channel capacity it defines the transfer rate from a media …read more
Experiments With A Bowden Extruder Filament Force Sensor
We were excited to learn that someone had started working with force sensors on filament extruders, especially after we posted about a recent development in filament thickness sensors.
[airtripper] primarily uses a Bowden extruder, and wanted to be a little more scientific in his 3D printing efforts. So he purchased a force sensor off eBay and modified his extruder design to fit it. Once installed he could see exactly how different temperatures, retraction rates, speed, etc. resulted in different forces on the extruder. He used this information to tune his printer just a bit better.
More interesting, [airtripper] used his …read more
Learn Resin Casting Techniques: Duplicating Plastic Parts
Resin casting lets you produce parts that would be otherwise impossible to make without a full CNC and injection molding set-up. It costs about as much as a 3d printer, 300 to 600 US dollars, to get a good set-up going. This is for raw material, resin, dye, pressure chamber, and an optional vacuum degassing set-up. A good resin casting set-up will let you produce parts which are stronger than injection molding, and with phenomenal accuracy, temperature resistance, and strength. I will be covering various techniques from the simple to advanced for using resin casting from a hacker’s perspective. …read more